Hey guys, I would like to get rid of the power brakes on my drag car (85 TA) and go with a manual setup, can someone tell what I need to get to do the refit?? I plan on putting in a fairly large cam over the winter and I don't want the vacuum assist on my brakes acting up.

 

You'll definitely need a different master cylinder.

Another option would be to convert to hydraulically assisted brakes, like on Astro vans. They use oil presure from the PS pump, and have a lot smaller power unit than the vacuum type.

 

thanks, I figured I'd need a different master cylinder I just don't know which. also the hydraulic option is out due to not having power steering either.

anybody else ?????

 

Just curious... why dump power brakes? They don't have a power robbing pulley like power steering does... is it just for weight?

 

Check out the options at www.mpbrakes.com. They may have some ideas for you. A 3/4" bore MC would get you closer to a realistic pedal effort for manual brakes. You're probably also have to work on the prop valve if you have drums in the rear.

 

the main reason I wanted to dump the power setup is because I plan on putting a fairly large cam later and don't want to risk dealing with the lack of vacuum.

 

there is a much simpler solution then converting to manual brakes.

you can get a electric vac pump.. GM used them on some smaller cars in the early 80s when it was found that the 4banger didnt have enough vac to support the brakes.... volvo has used them for years..


you can get them either for this application thru summit or other racing shops for about 300....

or you can get a replacement ment for one of the cars that had them stock for about 70 bucks...


they are also used when regular cars are converted into electric cars... since they are electric, there is no vac, so they use the pump to support the power accessories..... it keeps them from redesigning the entire braking system

 

I am swapping my race car over at this time. Here is what I am using. A master cylinder from a S-10 pick up. It has the same 24mm bore as a camaro but it has a reservoir that is level as the cylinder will sit level without the vac booster. I re-drilled my rod joint to be 2.5 inches from the pivot point instead of the normal 3.75 inches. This allows the rod to come in level and also increases the brake ratio. The outlet of the m/c is on the outside which makes it neater and more room to work on plugs and such. It has sae threads instead of metric. I am putting the combi valve against the wheel well just under the master. I have used a 1\4" strengthening plate between the master and the firewall. I needed to elongate the hole in the firewall up about 1\8" I like to have my seat back alot and I have short legs so redid the pedal bracket to allow the pedal to be 3 inches further back. It still allows the brake lite switch to hook up also. Shout if I can help any. Mine should be running in about 10 days.